Graphs can greatly benefit from getting map shapes from OSM database, instead of storing them on-wiki. This way, a graph could easily draw an outline of a country/region/municipality, and highlight individual regions with different colors.
T134084 will provide such a service, returning requested data as a topojson with each object having a Wikidata ID.
Graph can support this with:
"url": "geoshape:///ids=Q123,Q456,Q789"